1. Field of the Invention
The invention relates in general to a monopole antenna.
2. Description of the Related Art
In a small-sized communication product (such as a wireless router) or a communication product with built-in antenna, the antenna size affects the overall disposition of elements. Thus, the smaller the antenna, the more convenient the overall disposition of elements, and the smaller the size of communication products.
If it needs to have components of the antenna formed on the back of a circuit board to compensate the length of the antenna, dual-layer circuit board or multi-layer circuit board will be required, and the antenna cost will increase accordingly. If the antenna requires a ground terminal, the area/size of the antenna will increase.